The continuously growing herbal use in international market shows the beneficial use of herbal medicines as a complement to general pharmaceuticals. This situation has left consumers to wander around shelves to self-select different herbal and pharmaceutical supplements and medications separately, as they are in many cases not available on the same shelf of the same store. Patients struggle to get a good synergistic combination of herbal and pharmaceuticals; as in most cases there are no combinations available in ready-made combined forms. Most of the time consumers/patients remain unsuccessful in diminishing their ailment related sufferings and pain, which could be possible by using the benefits of both herbal medicines and conventional pharmaceuticals in a single formulation.
Combining herbals with pharmaceuticals is not a trivial undertaking in terms of product quality, consistency, and shelf life. Herbal extracts are not comprised of single molecule but are rather composed of a variety of molecules of different pharmaceutical classes. Herbal extracts constitute combinations of enzymes, co-enzymes, catalysts, volatile, fixed oils, flavonoids, amino acids, complexing agents, saponins, triterpinoids, tannins, sesquiterpenes, monoterpenes, etc. These chemical moieties are in many cases reactive to the active pharmaceuticals and cause their degradation in a small period of time, resulting in separation of layers, suspension, turbidity, discoloration, and in some cases change of the active pharmaceuticals into a toxic material.
This complex situation needs a pre-study of the compatible herbals selection, optimization of the quantity added of each herbal extract besides the addition of formulation excipients such as solubilizes, flavors, humectants, sweetening agents, and preservatives to the active pharmaceuticals; so that a stable formulation can be achieved.
Combining herbals with pharmaceuticals is not always successful but need to be proven by the results of a detailed chemical and microbiological stability studies. United States pharmacopeia provides acceptance criteria in terms of potency of the active pharmaceuticals, and the absence of microbiological growth during the label claimed shelf life. The average shelf life for a liquid formulation is eighteen months. During the shelf life product must maintain its physicochemical attributes within USP acceptance criteria. Shelf stability is not only important but a robust manufacturing technique with detailed steps is required to avoid complexation, suspension, loss of flavoring agents, volatiles, mixing of oils with water, avoiding complexation leading to precipitation, separation of layers, etc.
As such, considering the foregoing, it may be appreciated that there continues to be a need for novel and improved devices and methods for combining herbal extracts with pharmaceutical compositions.